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칼릭스아렌 포로젠을 이용한 다공성 박막의 초기 나노기공 형성과정에 관한 연구

A study on the Initial Nanopore Formation in the Calix Arene Based Porogen Templated Porous Thin Film

  • 김도헌 (공주대학교 천안공과대학 신소재공학부) ;
  • 임진형 (공주대학교 천안공과대학 신소재공학부)
  • Kim, Do-Hun (Division of Advanced Materials Engineering, Kongju National University) ;
  • Yim, Jin-Heong (Division of Advanced Materials Engineering, Kongju National University)
  • 발행 : 2011.10.01

초록

다공성 구조로 되어있는 차세대 저유전 박막(k<2.0)의 나노 기공의 초기 형성 과정을 이해하기 위하여 실세스퀴옥산(silsesquioxane; SSQ) 매트릭스에서 분산된 4-tert-butyl calix[4]arene-O,O',O",O"'-tetraacetic acid tetraethyl ester(CA[4]) 포로젠이 열분해에 의해서 나노 기공으로 전환되는 과정을 Fourier Transform Infrared Spectroscopy(FT-IR)와 in-situ Position Annihilation Lifetime Spectroscopy(PALS) 연구를 통해 분석하였다. SSQ/CA[4] 하이브리드 시스템은 열 경화에 따라 효과적인 기공 구조의 균일한 박막을 제공하였다. SSQ/CA[4] 10, 20% 두 종류의 하이브리드 박막을 in-situ PALS 분석을 시행한 결과, CA[4] 포로젠의 분해 거동이 달랐다. SSQ/CA[4] 10% 하이브리드 박막은 $300^{\circ}C$ 이상부터 단분자 포로젠으로부터 기인한 메조포어(~1.5 nm)가 생성되기 시작하였으나, SSQ/CA[4] 20% 하이브리드 박막은 상대적으로 낮은 온도인 $250^{\circ}C$부터 상태로 CA[4] 분자들이 자가 조립된 마이셀로부터 기인한 메조포어(2.5~3.0 nm)가 생성되었다. 이는 SSQ/CA[4] 20% 하이브리드 박막에서 생성된 기공의 구조가 매우 연결된 상태이기 때문에 초기에 포로젠이 분해되었을 때, 분해된 분자조각들이 쉽게 박막 외부로 빠져나올 수 있기 때문이라고 생각된다.

Fourier Transform Infrared Spectroscopy and in-situ Position Annihilation Lifetime Spectroscopy(PALS) analysis of hybrid film, which consist of silsesquioxane(SSQ) and 4-tert-butyl calix[4]arene-O,O',O",O'"-tetraacetic acid tetraethyl ester(CA[4]) have been investigated in order to understand initial formation of nanopore in the next generation porous low-k dielectrics(k < 2.0). SSQ/CA[4] can provide effective homogeneous thin film having porous structure. The porogen decomposition behavior were completely different in the two kinds of SSQ/CA[4] based hybrid film (i.e. SSQ/CA[4] 10 and SSQ/CA[4] 20%). Relatively small pores(1.5 nm) come from dispersion of uni-molecular CA[4] in the SSQ matrix have been generated at $300^{\circ}C$, while mesopores(2.5~3.0 nm) induced from self assembled CA[4] have been generated at $250^{\circ}C$. It might be due to highly interconnected structure of SSQ/CA[4] 20% hybrid thin film resulting in facile evacuating of decomposed fragment of CA[4] molecule.

키워드

참고문헌

  1. Corma, A., "From Microporous to Mesoporous Molecular Sieve Materials and Their Use in Catalysis," Chem. Rev., 97(6), 2373-2419(1997). https://doi.org/10.1021/cr960406n
  2. Kresge, C. T., Leonowicz, M. E., Roth, W. J., Vartuli, J. C. and Beck, J. S., "Ordered Mesoporous Molecular Sieves Synthesized by a Liquid-crystal Template Mechanism," Nature, 359, 710-712(1992). https://doi.org/10.1038/359710a0
  3. Yanagisawa, T., Shimizu, T., Kuroda, K. and Kato, C., "The Preparation of Alkyltrimethylammonium-kanemite Complexes and Their Conversion to Microporous Materials," Bull. Chem. Soc. Jpn., 63(4), 988-992(1990). https://doi.org/10.1246/bcsj.63.988
  4. Tamaki, R. and Chujo, Y., "Synthesis of IPN Polymer Hybrids of Polystyrene Gel and Silica Gel by an in-situ Radical Polymerization Method," J. Mater. Chem. 8(5), 1113-1115(1998). https://doi.org/10.1039/a708915e
  5. Lee, B., Park, Y.-H., Hwang, Y.-T., Oh, W., Yoon, J. and Ree, M., "Ultralow-k Nanoporous Organosilicate Dielectric Films Imprinted with Dendritic Spheres," Nature Materials, 4, 147-151(2005). https://doi.org/10.1038/nmat1291
  6. Kim, H. C., Wilds, J. B., Kreller, C. R., Volksen, W., Brock, P. J., Lee, V. Y., Magbitang, T., Hedrick, J. L., Hawker, C. J. and Miller, R. D., "Fabrication of Multi Layered Nanoporous Poly(methyl silsesquioxane)," Adv. Mater., 14(22), 1637-1639(2002). https://doi.org/10.1002/1521-4095(20021118)14:22<1637::AID-ADMA1637>3.0.CO;2-C
  7. Kohl, A. T., Mimna, R., Shick, R., Rhodes, L., Wang, Z. L. and Kohl, P. A., "Low-k, Porous Methyl Silsesquioxane and Spin- On-Glass," Electrochem. Solid-State Lett., 2(2), 77-79(1999). https://doi.org/10.1149/1.1390740
  8. de Theije, F. J., Balkenendl, A. R., Verheijen, M. A., Baklanov, M. R., Mogilnikov, K. P. and Furukawa, Y., "Structural Characterization of Mesoporous Organosilica Films for Ultralow-k Dielectrics," J. Phys. Chem. B., 107(18), 4280-4289(2003). https://doi.org/10.1021/jp027701y
  9. Yang, S., Mirau, P. A., Pai, C., Nalamasu, O., Reichmanis, E., Pai, J. C., Obeng, Y. S., Seputro, J., Lin, E. K., Lee, H., Sun, J. and Gidley, D. W., "Nanoporous Ultralow Dielectric Constant Organosilicates Templated by Triblock Copolymers," Chem. Mater., 14(1), 369-374(2002). https://doi.org/10.1021/cm010690l
  10. Lee, B., Oh, W., Hwang, Y., Park, Y.-H., Yoon, J., Jin, K. S., Heo, K., Kim, J., Kim, K.-W. and Ree, M., "Imprinting Well-controlled Nanopores in Organosilicate Dielectric Films; Triethoxysilyl-modified Six-armed Poly($\varepsilon$-caprolactone) and Its Chemical Hybridization with An Organosilicate Precursor," Adv. Mater., 17(6), 696-701 (2005). https://doi.org/10.1002/adma.200400919
  11. Lee, B., Oh, W., Yoon, J., Hwang, Y., Kim, J., Landes, B. G., Quintana, J. P. and Ree, M., "Scattering Studies of Nanoporous Organosilicate Thin Films Imprinted with Reactive Star Porogens," Macromolecules, 38(22), 8991-8995(2005). https://doi.org/10.1021/ma0501951
  12. Kim, J.-S., Kim, H.-C., Lee, B. and Ree, M., "Imprinting of Nanopores in Organosilicate Dielectric Thin Films with Hyperbranched Ketalized Polyglycidol," Polymer, 46, 7394-7402(2005). https://doi.org/10.1016/j.polymer.2005.06.024
  13. Yim, J.-H., Jeong, H.-D. and Pu, Y. S., "The Prepatation of Nanoporous Siloxane Films Using Saccharide Derivatives as New Porogen," Thin Solid Films, 476, 46-50(2005). https://doi.org/10.1016/j.tsf.2004.09.005
  14. Yim, J.-H., Lyu, Y.-Y., Jeong, H.-D., Song, S. A., Hwang, I.-S., Lee, J. H., Mah, S. K., Chang, S., Park, J.-G., Hu, Y. F., Sun, J. N. and Gidley, D. W., "The Preparation and Characterization of Small Mesopores in Siloxane-based Materials That Use Cyclodextrins as Templates," Adv. Func. Mater., 13(5), 382-386(2003). https://doi.org/10.1002/adfm.200304287
  15. Yim, J.-H., Seon, J.-B., Jeong, H.-D., Pu, Y. S., Baklanov, M. R. and Gidley, D. W., "Morphological Control of Nanoporous Films by the Use of Functionalized Cyclodextrins as Porogens," Adv. Funct. Mater., 14(3), 277-282(2004). https://doi.org/10.1002/adfm.200305019
  16. Yim, J.-H., Kim, J., Gidley, D. W., Vallery, R. S., Peng, H.-G., An, D. K., Choi, B., Park, Y.-K. and Jeon, J.-K., "Calixarene Derivatives as Novel Nanopore Generators for Templates of Nanoporous Thin Films," Macromol. Mater. Eng., 291, 369-376(2006). https://doi.org/10.1002/mame.200500370
  17. Gutsche, C. D., Dhawan, B., No, K. H. and Muthukrishnan, R., "Calixarene. 4. The Synthesis, Characterization, and Properties of the Calixarenes from p-tert-butylphenol," J. Am. Chem. Soc., 103(13), 3782-3792(1981). https://doi.org/10.1021/ja00403a028
  18. Cho, Y. L., Rudkevich, D. M. and Rebek Jr. J., "Expanded Calix [4]arene Tetraurea Capsules," J. Am. Chem. Soc., 122(40), 9868-9869(2000). https://doi.org/10.1021/ja002345n
  19. Alexandratos, S. D. and Natesan, S., "Synthesis and Ion-binding Affinities of Calix[4]arenes Immobilized on Cross-linked Polystyrene," Macromolecules, 34(2), 206-210(2001). https://doi.org/10.1021/ma0012550
  20. Lee, K. H. and Yim, J.-H., "Porous Low-dielectric Constant Thin Film with Controlled Solvent Diffusion," U.S. Patent No. 11, 263,867(2006).
  21. Baklanov, M. R., Mogilnikov, K. P., Polovinkin, V. G. and Dultsev, F. N., "Determination of Pore Size Distribution in Thin Films by Ellipsometric Porosimetry," J. Vac. Sci. & Technol. B. 18(3), 1385-1391(2000). https://doi.org/10.1116/1.591390
  22. Baklanov, M. R. and Mogilnikov, K. P., "Non-destructive Characterisation of Porous Low-k Dielectric Films," Microelectron. Eng., 64, 335-349(2002). https://doi.org/10.1016/S0167-9317(02)00807-9
  23. Maex, K., Baklanov, M. R., Shamiryan, D., Iacopi, F., Brongersma, S. and Yanovitskaya, Z. Sh., "Low Dielectric Constant Materials for Microelectronics," J. Appl. Phys. 93(11), 8793-8841 (2003). https://doi.org/10.1063/1.1567460
  24. Gidley, D. W., Peng, H. G. and Vallery, R. S., "Positron Annihilation as a Method to Characterize Porous Materials," Ann. Rev. Mat. Res. 36, 49-79(2006). https://doi.org/10.1146/annurev.matsci.36.111904.135144
  25. Gidley, D. W., Frieze, W. E., Dull, T. L., Sun, J., Yee, A. F., Nguyen, C. V. and Yoon, D. Y., "Determination of Pore-size Distribution in Low-dielectric Thin Films," Appl. Phys. Lett. 76(10), 1282-1284 (2000). https://doi.org/10.1063/1.126009
  26. Gidley, D. W., Frieze, W. E., Yee, A. F., Dull, T. L., Ho, H.-M. and Ryan, E. T., "Positronium Annihilation in Mesoporous Thin Films," Phys. Rev. B, Rapid Comm. 60(8), R5157-R5160(1999). https://doi.org/10.1103/PhysRevB.60.R5157
  27. Dull, T. L., Frieze, W. E., Gidley, D. W., Sun, J. N. and Yee, A. F., "Determination of Pore Size in Mesoporous Thin Films from the Annihilation Lifetime of Positronium," J. Phys. Chem. B. 105(20), 4657-4662(2001). https://doi.org/10.1021/jp004182v
  28. Liu, W. C., Yang, C. C., Chen, W. C., Dai, B. T. and Tsai, M. S., "The Structural Transformation and Properties of Spin-on Poly (Silsesquioxane) Films by Thermal Curing," J. Non-Cryst. Solids., 311, 233-240(2002). https://doi.org/10.1016/S0022-3093(02)01373-X